Resin composition

ABSTRACT

Resin compositions having excellent heat resistance, izod impact strength, rigidity and dimensional resistance and the like, applied in the fields of the automobile, electric and electronic, and the like industries. The resin composition comprising: a) a resin in which 30 to 98 mole % of the component (I) are contained in the whole polymer and 70 to 2 mole % of the component (II) are contained in the whole polymer, its weight-average molecular weight converted into that of polystyrene being 1×10 3  or more to 5×10 6  or less, and b) an olefin resin; then the a)/b) content being 5/95 to 99/1 as a weight ratio, ##STR1## wherein R 1  is an alkyl group having 1 to 18 carbon atom(s) or a cycloalkyl group having 3 to 12 carbon atoms; and ##STR2## wherein R 2  is hydrogen or an alkyl group having 1 to 8 carbon atom(s), and R 3  and R 4  is an alkyl group having 1 to 8 carbon atoms.

This is a divisional of application Ser. No. 07/967,879, filed Oct. 29,1992 now U.S. Pat. No. 5,424,380.

BACKGROUND OF THE INVENTION

1. Field of the Invention

The present invention relates to a resin composition comprising anN-alkyl-substituted maleimide/olefin copolymer and a specified resin,which has excellent heat resistance, rigidity, izod impact strength,weather resistance and dimensional resistance.

2. Description of the Related Art

Recently, various high-performance resins have been actively developedwith progress of the polymer-alloying technology. This development haverapidly enabled us to plasticize materials which had not been applied.In particular, the plasticization has intensively studied in the fieldof the automobile, electric and electronic industries and, for example,the plasticization of the automobile body which has been made up bysteels is studied. Although the alloy of polycarbonates and ABS has beenonce adopted, there are problems on productivity, color tone and thelike because the alloy with poor heat resistance is coated off-line.

GE Company has developed an alloy of a polyamide and a polyphenyleneoxide. Although this material has improved water absorption propertiesas well as changes in dimension and physical properties compared withthe polyamide itself, there are many problems of insufficient physicalproperties, as well as low rigidity, poor weather resistance and thelike which derive from some defects of amides.

Having low weather resistance and other good physical properties,polyesters such as a polybutylene terephthalete have been studied toblend with a variety of resins such as a polyphenylene oxide, apolycarbonate and an elastomer. However, these blending does not providethe resins with satisfactory, combined properties of heat resistance,rigidity, izod impact strength and the like.

On the other hand, maleimide copolymers with large heat resistance havebeen studied for various methods of blending. For example, a method inwhich methyl methacrylate is copolymerized with anN-aromatic-substituted maleimide is disclosed in Japanese PatentPublication No. 43-9753, Japanese Patent Laid-Open Nos. 61-141715,61-171708 and 62-109811; and a method in which styrene resins arecopolymerized with an N-aromatic-substituted maleimide is disclosed inJapanese Patent Laid-Open Nos. 47-6891, 61-76512 and 61-276807. Althoughthe resins obtained by these methods, however, have larger heatresistance with the increased content of N-aromatic-substitutedmaleimides, there are problems that they are very fragile, poor inprocessability and colored easily. Thus these N-aromatic-substitutedmaleimides are only blended in a small amount as heat resistancemodifiers to acrylonitrile/butadiene/styrene (ABS) resin.

For prevention of decrease in mechanical strength of the resins byincreasing maleimide units, for example, a method for graft-polymerizingphenylmaleimide and styrene to rubber-like material, or a method forkneading them with rubber-like material is described in, for example,Japanese Patent Laid-Open Nos. 58-206657, 59-11322 and 59-49255. Sincethe heat resistance and rigidity of the resins was decreased byintroducing rubber components using these methods to increase their izodimpact strength, it is difficult to satisfy the heat resistance, izodimpact strength and rigidity at the same time. Further, use of theresins with light color is limited because of coloring molded objects.Compositions of such materials and polyamide resins are also describedin Japanese patent Laid-Open Nos. 62-59647 and 62-179546, thought it wasalso difficult to satisfy the heat resistance, izod impact strength andrigidity of them at the same time.

Although N-alkyl-substituted maleimide/olefin copolymers are interestingpolymers which have the properties such as good heat resistance andweather resistance, high rigidity, and practical mechanical strength, itis desired to further improve the izod impact strength of the resins,and improvement of changes in physical properties and change indimension by water absorption is also desired. Further, Japanese PatentPublication No. 49-12576 describes a resin composition ofmaleimide-olefin compound, a simple blend, is not made up by a reaction(interaction), so that it is improved a little for flexural stiffnessand izod impact strength.

SUMMARY OF THE INVENTION

Accordingly, an object of the present invention is to provide resincompositions with excellent heat resistance, rigidity, izod impactstrength, weather resistance, dimensional resistance and the like.

As a result of intensive research to overcome this problem, the presentinventors have found a resin comprising an N-alkyl-substitutedmaleimide/olefin copolymer and a specified resin, which satisfies theabove-mentioned object to achieve the present invention.

In order to achieve the object, according to one aspect of the presentinvention, there is provided a heat-resistance resin compositioncomprising:

a) a resin in which 30 to 98 mole % of the following component (I) arecontained in the whole polymer and 70 to 2 mole % of the followingcomponent (II) are contained in the whole polymer, its weight-averagemolecular weight converted into that of polystyrene being 1×10 or moreto 5×10⁶ or less, and b) an olefin resin; then the a)/b) content being5/95 to 99/1 as a weight ratio, ##STR3## wherein R₁ is an alkyl grouphaving 1 to 18 carbon atom(s) or a cycloalkyl group having 3 to 12carbon atoms; and ##STR4## wherein R₂ is hydrogen or an alkyl grouphaving 1 to 8 carbon atom(s), and R₃ and R₄ is an alkyl group having 1to 8 carbon atoms.

According to another aspect of the present invention, there is provideda resin composition comprising: a) the same resin as theabove-mentioned, and b) an modified elastomer, the a)/b) content being5/95 to 99/1 as a weight ratio; a resin composition comprising: a) 1 to99% by weight of the same resin as the above-mentioned, and b) 1 to 99 %by weight of a polyamide resin, and c) 0 to 40% by weight of anelastomer; and a resin composition comprising: a) 1 to 99% by weight ofthe same resin as the above-mentioned; and b) 1 to 99% by weight of apolyester resin, and c) 0 to 40% by weight of an elastomer.

As described clearly in the following Examples, since the resincompositions of the present invention have excellent heat resistance,izod impact strength, rigidity and dimensional resistance and goodmechanical strength, they are usefully applied in the various fields ofthe automobile, electric and electronic, aeronautic and shipping,residential, medical, food and the like industries.

BRIEF EXPLANATION OF THE DRAWINGS

FIG. 1 is a microphotograph (TEM) of an interface of the sample obtainedby Example 9 and FIG. 2 is a microphotograph (TEM) of an interface ofthe sample obtained by Comparative Example 5.

DETAILED DESCRIPTION OF THE INVENTION AND PREFERRED EMBODIMENTS

The resin compositions of the present invention have combined excellentheat resistance, rigidity, izod impact strength, weather resistance anddimensional resistance. Then the present invention is illustrated below.

The resin a) making up the resin composition of the present inventioncan be prepare by radical polymerization of the N-alkyl-substitutedmaleimide and the olefin.

Examples of the N-alkyl-substituted maleimide include N-methylmaleimide,N-ethylmaleimide, N-n-propylmaleimide, N-i-propylmaleimide,N-n-butylmaleimide, N-i-butylmaleimide, N-s-butylmaleimide,N-t-butylmaleimide, N-n-pentylmaleimide, N-n-hexylmaleimide,N-n-heptylmaleimide, N-n-octylmaleimide, N-laurylmaleimide,N-stearylmaleimide, N-cyclopropylmaleimide, N-cyclobutylmaleimide,N-cyclohexylmaleimide and the like; and more preferablyN-methylmaleimide, N-ethylmaleimide, N-isopropylmaleimide orN-cyclohexylmaleimide. Further, one or more compounds of them can beused in combination.

Examples of the olefin include isobutene, 2-methyl-1-butene,2-methyl-1-pentene, 2-methyl-1-hexene, 1-methyl-1-heptene, 1-isooctene,2-methyl-1-octene, 2-ethyl-1-pentene, 2-methyl-2-butene,2-methyl-2-pentene, 2-methyl-2-hexene and the like, and more preferablyisobutene. Further, one or more compounds of them can be used incombination.

The content of the component (I) is 30 to 98 mole %, preferably 40 to 85mole %, and more preferably 45 to 75 mole %. When the content of thecomponent (I) is more than 98 mole %, fragile polymers are prepared. Butin contrast when the content is less than 30 mole %, polymers withdecreased heat resistance are undesirably prepared. Such the content ofthe components may be appropriately determined by adjusting the amountof the above-mentioned compounds to be used in the reaction of them.

The above-mentioned resin a) may preferably have been further modifiedwith reactive groups. Examples of these reactive groups includecarboxylic acid and derivatives thereof, acid anhydride, epoxy, amino,hydroxyl, thiol alkoxysilyl and isocyanate groups. Then the content ofthe reactive group is 0 to 25 mole %, preferably 0.01 to 20 mole %, andmore preferably 0.02 to 5 mole %. When the content of the reactive groupis more than 25 mole %, a resin tends to be undesirably prepared, withdecreased heat stability and mechanical strength.

The thus modified resins can be prepared by copolymerization or graftpolymerization of the following monomers: for example, maleic anhydride,citraconic anhydride, itaconic anhydride, acrylic acid, methacrylicacid, itaconic acid, glycidyl acrylate, glycidyl methacrylate,aminoethyl acrylate, aminoethyl methacrylate, hydroxoyethyl acrylate,hydroxyethyl methacrylate, triethoxysilylpropyl acrylate,triethoxysilylpropyl methacrylate, aminostyrene, allylamine and thelike.

Further, reactive groups can be introduced to polymers at their endsusing initiators with the reactive groups such as 4,4'-azobis(4-cianovaleric acid), 2,2'-azobis(2-cianopropanol) and2,2'-azobisisobutylamide, or using chain transfer agents with thereactive groups such as mercaptoacetic acid and mercaptopropionic acid.

As described below, if the resin a) is obtained by subjecting acopolymer of maleic anhydride and an olefin to after-imidation,adjustment of the imidation amount can make acid anhydride units remain.

These reactive groups can be selected depending on the reactive groupsof the specified resin described below.

If necessary, other monomers may be subjected to copolymerizationwithout departing from the objects of the present invention. Examples ofthe other vinyl monomers include styrene, α-methylstyrene, vinyltoluene,1,3-butadiene, isoprene and halogen-substituted derivatives thereof;methacrylic esters such as methyl methacrylate, ethyl methacrylate,cyclohexyl methacrylate, phenyl methacrylate and benzyl methacrylate;acrylic esters such as methyl acrylate, ethyl acrylate, butyl acrylate,cyclohexyl acrylate, phenyl acrylate and benzyl acrylate; vinyl esterssuch as vinyl acetate and vinyl benzoate; vinyl ethers such as methylvinyl ether, ethyl vinyl ether, propyl vinyl ether and butyl vinylether; and one or more compounds selected from the group consisting ofvinyl chloride, vinylidene chloride, maleic anhydride,N-phenylmaleimide, N-carboxyphenylmaleimide, acrylonitrile, ethylene,propylene, 1-butene, 2-butene and 1-hexene.

For polymerization of these monomers, any methods for the publicly knownpolymerization, for example, bulk polymerization, solutionpolymerization, suspension polymerization and emulsion polymerizationcan be applied.

Examples of polymerization initiators include organic peroxides such asbenzoyl peroxide, lauryl peroxide, octanoil peroxide, acethyl peroxide,di-t-butyl peroxide, t-butyl cumpyl peroxide, dicumyl peroxide, t-butylperoxyacetate and t-butylperoxy benzoate; or azo initiators such as2,2'-azobis(2,4-dimethylvaleronitrile), 2,2'-azobis(2-butylonitrile),2,2'-azobisisobutylonitrile, dimethyl-2,2'-azobisisobutylate and1,1'-azobis(cyclohexane-1-carbonitrile).

Examples of the solvents which can be used in the solutionpolymerization include benzene, toluene, xylene, ethylbenzene,cyclohexane, dioxane, tetrahydrofuran, acetone, methyl ethyl ketone,dimethylformamide, isopropyl alcohol, butyl alcohol and the like.

The polymerization temperature can be appropriately adjusted dependingon the decomposition temperature of the initiators, then it is usuallypreferred to adjust between 40° and 150° C.

The above-mentioned resins may be also obtained by subjecting the resinsfrom copolymerization of maleic anhydride and olefins to after-imidationwith alkylamine and the like. The after-imidation is performed bymelting, for example, a maleic anhydride/isobutene copolymer, ordissolving or dispersing the copolymer in alcoholic solvents such asmethanol, ethanol and propanol, or aromatic solvents such as benzene andtoluene; then by reacting with primary amines such as methyl amine andthe like at a temperature of 100° to 350° C.

Then, weight-average molecular weight (MW) of the resin prepared can bedetermined by gel permeation chromatography (GPC). The molecular weightof a maleimide copolymer is 1×10³ or more to 1×10⁶ or less, and morepreferably 1×10⁵ or more to 1×10⁶ or less. If the molecular weight ismore than 5×10⁶, the resulting resin tends to have poor moldingproperties; and if that is less than 1×10³, the resin tends to becomefragile.

Since those N-alkyl-substituted maleimide/olefin copolymers arematerials which have excellent heat resistance, good weather resistance,practical mechanical strength and very high rigidity, compositions withbetter physical properties can be obtained by use of those materials.

Examples of the olefin resins used in the resin compositions of thepresent invention include a polyethylene, a polypropylene,poly-4-methyl-1-pentene and modified substances thereof. Thepolyethylene used in the compositions of the present invention, which isa resin mainly composed by ethylene units, is defined as a polymer inwhich 60 mole % or more, preferably 80 mole % or more, and morepreferably 90 mole % or more of the ethylene units are contained in thewhole resin.

The polyethylenes which can be used as olefin resins according to thepresent invention may be subjected to copolymerization or graftpolymerization with other unsaturated monomers capable ofcopolymerization, for example, α-olefins such as propylene, 1-butene and1-hexene; vinyl ethers; vinyl esters such as vinyl acetate and vinylpropyonate; acrylic esters; methacrylic esters; acrylonitrile and thelike, the amounts of which are in the ranges of 0 to 40 mole %,preferably 0 to 25 mole %, and more preferably 0 to 15 mole %.

Then, these polyethylenes may preferably be modified by various reactivegroups, examples of which include acid anhydride, carboxylic acid andderivatives thereof, and hydroxyl, thiol, amino, epoxy, alkoxysilyl andisocyanate groups. Those modifications are performed by publicly knowncopolymerization, graft polymerization and the like using, for example,maleic anhydride, citraconic anhydride, itaconic anhydride, acrylicacid, methacrylic acid, hydroxyethyl methacrylate, aminoethylmethacrylate, glycidyl methacrylate, glycidyl acrylate and the like. Theamount of the modified polyethylene with these reactive groups is 0 to25 mole %, preferably 0.01 to 15 mole %, and more preferably 0.02 to 5mole %.

The polypropylenes which can be used as olefin resins according to thepresent invention are those containing 80 mole % of polypropylene unitsin the whole resin, and may be subjected to copolymerization or graftpolymerization with other unsaturated monomers capable ofcopolymerization, for example, α-olefins such as ethylene, 1-butene and1-hexene; vinyl ethers; vinyl esters such as vinyl acetate and vinylpropyonate; acrylic esters; methacrylic esters; acrylonitrile and thelike, the amounts of which are in the range of 0 to 20 mole %.

Then, these polypropylenes may be modified by various reactive groups,examples of which include acid anhydride; carboxylic acid andderivatives thereof, and hydroxyl, amino epoxy, alkoxysilyl groups andthe like. Those modifications are performed by publicly knowncopolymerization, graft polymerization and the like using, for example,maleic anhydride, acrylic acid, methacrylic acid, hydroxyethylmethacrylate, aminoethyl methacrylate, glycidyl methacrylate and thelike, preferably a modified polypropylene grafted with maleic anhydride,acrylic acid, etc. The amount of the modified polypropylene with thesereactive groups is 0 to 20 mole %, and preferably 0.01 to 5 mole %.Further, a poly-4-methyl-1-pentene which can be used as an olefin resinaccording to the present invention, a polymer mainly composed by4-methyl-1-pentene units, may be also modified by various reactivegroups.

Furthermore, to the resin composition of the present invention may bealso added a third component capable of reacting with the reactive groupof the maleimide copolymer and/or olefin. Examples of the combinationinclude maleic anhydride-modified maleimide copolymer/maleicanhydride-modified polyethylene/diamines such as diaminodiphenyl etherand the like or polyamine compounds such as a polyallylamine and thelike, and carboxyl-modified maleimide copolymer/carboxyl-modifiedpolypropylene/diepoxy compounds or epoxy resins such as diglycidylphthalate and the like. In the resin compositions of the presentinvention, the content (weight ratio ) of the above-mentioned resin a )N-alkyl-substituted maleimide/olefin copolymer and the resin b)polyolefin is 5-99:95-1; preferably 50-99:50-1, and more preferably70-98:30-2.

Being modified substances of viscoelastic elastomers having glasstransition temperatures of 10° C. or less, the modified elastomers inone aspect of the present invention are, but not limited to, modifiedsubstances such as diene elastomers and hydrogenated elastomers thereof,olefin elastomers, acrylic elastomers, silicone elastomers, fluorineelastomers, urethane elastomers, ester elastomers and amide elastomers.These elastomers may be modified by various reactive groups, examples ofwhich include acid anhydride, carboxylic acid and derivatives thereof,and hydroxyl, amino, epoxy, alkoxysilyl, isocyanate groups and the like,more specifically, maleic anhydride, citraconic anhydride, itaconicanhydride, acrylic acid, methacrylic acid, itaconic acid, fumaric acid,glycidyl acrylate, glycidyl methacrylate, 2-aminoethyl acrylate,2-aminoethyl methacrylate, 2-hydroxyethyl acrylate, 2-hydroxyethylmethacrylate, triethoxysilylpropyl acrylate, triethoxysilylpropylmethacrylate, allylamine, etc. Those modifications are performed by apublicly known method such as copolymerization or graft polymerization.

Then, examples of modified elastomers include acid anhydride-modifiedsubstances, epoxy-modified substances or hydroxy-modified substances ofdiene elastomers such as a polybuthadiene, a styrene/buthadiene rubber,an acrylonitrile/buthadiene rubber, an acrylonitrile/styrene/buthadienerubber, methyl methacrylate/styrene/buthadiene, an isopropylene rubberand a chloroprene rubber; acid anhydride-modified substances,epoxy-modified substances or carboxy-modified substances of hydrogenateddiene elastomers; acid anhydride-modified substances, epoxy-modifiedsubstances, carboxy-modified substances or hydroxy-modified substancesof olefin elastomers such as an ethylene/propylene. (ethylidenenorbornene) rubber, a butyl rubber, an ethylene/vinyl acetate rubber andethylene/methyl acrylate; acid anhydride-modified substances,epoxy-modified substances or amino-modified substances of an acrylicrubber mainly composed by ethyl acrylate, epoxy-modified substances,hydroxy-modified substances or amio-modified substances of apolysiloxane; and the like.

Selection of those elastomer components provides the resin compositionswith physical properties such as low temperature izod impact strength,oil resistance, molding properties and weather resistance. The use ofmodified substances of diene elastomers provides them with lowtemperature izod impact strength, and the modified substances of olefinelastomers and acrylic elastomers provide them with weather resistanceand izod impact strength.

The reactive group content of the whole elastomer is 0.001 to 30 mole %,preferably 0.01 to 20 mole %, and more preferably 0.05 to 5 mole %.

Then, to the resin composition of the present invention may be alsoadded a third component capable of reacting with the reactive group ofthe maleimide copolymer and/or modified elastomer. Examples of thecombination include maleic anhydride-modified maleimide copolymer/maleicanhydride-modified elastomer/diamino compounds such as diaminodiphenylether and the like, and hydroxy-modified maleimidecopolymer/hydroxy-modified elastomer/diepoxy compounds such asdiglycidyl phthalate and the like.

The polyamide resins making up the resin compositions of the presentinvention are polyamides obtained from the ring opening polymerizationof lactam such as ε-caprolactam and ω-dodecalactam; polyamides obtainedfrom amino acids such as 6-aminocapronic acid, 11-aminoundecanoic acidand 12-aminododecanoic acid; polyamides obtained from aliphatic,cycloaliphatic and aromatic diamines such as ethylenediamine,tetramethylenediamine, hexamethylenediamine, undecamethylenediamine,dodecamethylenediamine, 2,2,4-trimethylhexamethylenediamine, 1,3- or1,4-bis(aminomethyl)cyclohexane, bis(4,4-aminocyclohexyl)methane,methaxylenediamine and paraxylenediamine, and aliphatic, cycloaliphaticand aromatic dicarboxylic acid such as adipic acid, suberic acid,sebacic acid, dodecane diacid, 1,4-cyclohexnedicarboxylic acid,isophthalic acid and terephthalic acid, and copolymers and mixturethereof. Among them, nylon 6, nylon 66, nylon 610, nylon 612, nylon 11,nylon 12, nylon 46 are useful.

In general, publicly known melt polymerization, solution polymerization,solid phase polymerization and combined polymerizations thereof can beadopted as the methods for polymerizing these polyamides. Generally, themolecular weight of the polyamides preferably are, but not limited to,10000 or more.

Some elastomers are preferably blended to the resin compositions of thepresent invention. The elastomers of macromolecular compounds havingglass transition temperatures of 10° C. or less, which are used in resincompositions of the present invention, include olefin elastomers, dieneelastomers and hydrogenated elastomers thereof, acrylic elastomers,silicone elastomers, fluorine elastomers and the like. The olefinelastomers and acrylic elastomers are preferred in terms of weatherresistance, mechanical strength and the like.

Examples of olefin elastomers include a butyl rubber and an ethyleneelastomer. The butyl rubber is mainly composed by a polyisobutylene. Theethylene elastomer, a polyethylenes and copolymer thereof, is composedby 50 mole % or more, preferably 75 mole % or more of ethylene units inthe whole elastomer. Examples of other unsaturated monomers capable ofcopolymerizing with ethylene include α-olefins such as propylene,1-butene and 1-hexene, vinyl ethers, vinyl esters such as vinyl acetateand vinyl propyonate, acrylic esters, methacrylic esters andacrylonitrile. They may be formed by copolymerization or graftpolymerization according to publicly known methods.

The acrylic elastomer is mainly composed by acrylic esters such asmethyl ester, ethyl ester or butyl ester of acrylic acid. Examples ofother components capable of copolymerizing with them include aromaticmonomers such as styrene, methacrylic esters, vinyl acetate and thelike.

Those elastomers are preferably modified by various reactive groups.Examples of the reactive groups include acid anhydride, carboxylic acidand derivatives thereof, and hydroxyl, thiol, amino, epoxy, alkoxysilyl,isocyanate groups and the like. Those modifications are performed bypublicly known copolymerization, graft polymerization and the likeusing, for example, maleic anhydride, citraconic anhydride, itaconicanhydride, acrylic acid, methacrylic acid, itaconic acid, hydroxyethylmethacrylate, aminoethyl methacrylate, glycidyl methacrylate, glycidylacrylate, 3-(triethoxysilyl)propyl methacrylate and the like. The amountof the modified elastomer with these reactive groups is 0 to 25 mole %,preferably 0.01 to 15 mole %, and more preferably 0.02 to 5 mole %.

More practical examples of these elastomers include anehtylene/propylene rubber and acid anhydride-modified substance thereof,a carboxylic acid-modified substance, a glycidly methacrylate-modifiedsubstance, an ethylene/acrylic acid copolymer, an ethylene/glycidylmethacrylate copolymer, an ethylene/ethyl acrylate/glycidyl methacrylatecopolymer, an ethylene/ethyl acrylate/maleic anhydride copolymer, anethylene/vinyl acetate/maleic anhydride copolymer, an ethylacrylate/glycidyl methacrylate copolymer, and ethyl acrylate/butylacrylate/maleic anhydride copolymer and the like.

In the resin compositions of the present invention, the content (weightratio) of an N-alkyl-substituted maleimide/olefin copolymer, a polyamideresin and an elastomer is 1-99:99-1:0-40, preferably 5-95:95-5:0-30, andmore preferably 10-75:90-25:1-25. When the content of the maleimidecopolymer is 1% by weight or less, a resin with poor heat resistance andlow rigidity is undesirably obtained. On the other hand, when theelastomer content is 40% by weight or more, a resin with possiblydecreased heat resistance and rigidity is undesirably obtained.

Examples of the polyester resin used in the resin composition of thepresent invention include a polybutylene terephthalate, a polyethyleneterephthalate, a polyacrylate, a liquid-crystalline polyester and thelike.

Examples of the elastomers used in the resin compositions of the presentinvention include diene elastomers and hydrogenated substances thereofsuch as a polybuthadiene, a styrene/buthadiene copolymer, anacrylonitrile/buthadiene copolymer, an acrylonitrile/styrene/buthadienecopolymer, a methyl methacrylate/styrene/buthadiene copolymer, apolyisopulene and a polychloreprene; olefin elastomers such as anethylene/propylene (ethylidene norbornene ) rubber, a butyl rubber, anethylene/vinyl acetate rubber and ethylene/methyl acrylate; an acrylicrubber mainly composed by acrylic ester, silicone elastomers, fluorineelastomers, urethane elastomers, ester elastomers, amido elastomers andthe like.

The above-mentioned elastomers are preferably modified by the reactivegroups such as acid anhydride, carboxylic acid, epoxy, hydroxyl, amino,alkoxysilyl and isocyanate groups. Then the content of the reactivegroup is 0.001 to 30 mole % of the whole elastomer, preferably 0.01 to20 mole %, and more preferably 0.05 to 5 mole %.

Then, various kinds of catalysts may be added to this system in order topromote the reaction of a maleimide copolymer, polyester resin andelastomer.

Further, dispersibility and compatibility of each component may beimproved by blending polyamino compounds such as a diaminodiphenylether, polyepoxy compound; such as a resorcin glycidyl ether and adiglycidyl phthalic ehter; components capable of reacting with amaleimide copolyers, a polyester resin, an elastomer and the like.

In the present invention, the content (weight ratio) of analkylmaleimide/olefin copolymer, a polyester resin and an elastomer is1-99:99-1:0-40, preferably 5-95:95-5:5-40, and more preferably10-75:90-25:10-30. When the content of the alkylmaleimide/olefincopolymer is 1% by weight or less, a resin with poor heat resistance andlow rigidity is undesirably obtained. On the other hand, when theelastomer content is 40% by weight or more, a resin with low rigidity isundesirably obtained.

To the resin compositions of the present invention may be blended otherresins, for example, an acrylic resin, a polystyrene, a vinyl chlorideresin, a polyphenylene ether, a polyacetal, a polyamide, a polyester, apolyphenylene sulfide, a polyimide, polycarbonate, a polysulfone and afluorine resin, and an elastomer such as a diene elastomer, an olefinelastomer, acrylic elastomer, an urethane elastomer, a fluorineelastomer or a silicone elastomer, and a random, block and graft polymerthereof and the like.

Further, the above-mentioned maleimide and olefins are polymerized inthe presence of rubber-like polymers, and the resulting graft polymersmay be used.

At the time of practical use, to the resin compositions of the presentinvention may be blended inorganic and organic fillers such as variouskinds of dye, glass fibers whose surface may be treated, carbon fibers,potassium titanate, asbestos, silicone carbide, ceramic fibers, metalfibers, silicone nitride, barium sulfate, potassium sulfate, kaolin,clay, pyrophyllite, zeolite, mica, talc, ferrite, calcium silicate,calcium carbonate, magnesium carbonate, antimony trioxide, zinc oxide,titanium oxide, iron oxide, glass balloon and aramide fiber; heatstabilizers such as hindered phenol and organic phosphoric ester;ultraviolet light stabilizer of benzotriazol series or hindered amineseries and the like; flame retarders, blowing agents, antistatic agents,various kinds of lubricant and the like. Further, the molding objectsmay be plated, coated, printed and the like.

Though not limited, the methods for preparing the resin compositions ofthe present invention include, for example, a method in which anN-alkyl-substituted maleimide/olefin copolymer in the form of powder orpellet and other additives are blended, or they are supplied in anextruder without blending and then melt-kneaded.

EXAMPLES

The resin compositions of the present invention are illustrated withreference to the following examples, but the invention is not intendedto be limited only to these following examples.

The molecular weights of the prepared polymers were calculated byconverting into those of polystyrenes using GPC (HLC-802A, TOSOHCORPORATION).

The composition of the prepared polymers was mainly determined byelemental analysis and ¹ N-NMR spectrometry.

The weather resistance of the prepared polymers was estimated fromchanges in physical properties and appearance after irradiation for 200hours using a Weather meter (Suga Test Apparatus Co., Ltd.).

The heat distortion temperature, flexural stiffness and flexuralmodulus, and izod impact strength of the prepared polymers weredetermined according to ASTM D648, ASTM D790 and ASTM D256,respectively.

(Reference Example 1)

Preparation of N-alkyl-substituted maleimide/olefin copolymers

A-1

Into an autoclave (50 liters) having a stirring machine,nitrogen-introducing tube, thermometer and deaerating tube were placed2780 g (25 mole) of N-methyl maleimide, 71 g (0.5 mole) of glycidylmethacrylate, 3.2 g (0.02 mole) of 2,2'-azobisisobutyronitrile (AIBN)and 35 liters of dioxane. After the mixture was purged with nitrogenseveral times, 5610 g (100 mole) of isobuthene was added, and thenreacted at 60° C. for 12 hours.

The reaction contents were poured into ethanol to separate out apolymer. The polymer was dried under reduced pressure at 60° C. for 24hours, with the yield of 4175 g. By subjecting the resulting polymer toelemental analysis and ¹ N-NMR spectrometry, it was found that theprepared polymer contained the maleimide units of 49.5 mole % andglycidylmethacrylate units of 0.8 mole %. The resulting polymer had amolecular weight (MW) of 213000.

A-2

Into the same reactor as used in A-1 were placed 2780 g (25 mole) ofN-methyl maleimide, 48 g (0.4 mole) of 4-aminostyrene, 3.2 g (0.02 mole)of 2,2'-azobisisobutyronitrile (AIBN) and 35 liters of dioxane. Afterthe mixture was purged with nitrogen several times, 5610 g (50 mole) ofisobuthene was added, and then it was reacted at 60° C. for 12 hours.

The reaction contents were poured into ethanol to separate out apolymer. The polymer was dried under reduced pressure at 60° C. for 24hours, with the yield of 4182 g. By subjecting the resulting polymer toelemental analysis and ¹ N-NMR spectrometry, it was found that theprepared polymer contained the maleimide units of 50.0 mole % and4-aminostyrene units of 1.0 mole %. The resulting polymer had amolecular weight (MW) of 250000.

A-3

An N-cyclohexyl maleimide/glycidyl methacrylate/isobuthene copolymer wasprepared by the same method as in A-1 except that N-cyclohexyl maleimidewas used in place of N-methyl maleimide.

The results of the prepared polymer by elemental analysis showed thepolymer contained maleimide units of 51 mole % and glycidylmethacrylateunits of 0.6 mole %. The resulting polymer had a molecular weight (MW)of 277000.

A-4

An N-methyl maleimide/isobuthene copolymer was prepared by the samemethod as used in A-1 without glycidyl methacrylate. The preparedpolymer had maleimide units of 50 mole % and a molecular weight (MW) of240000.

B-1

A copolymer consisting of ethylene units of 91.86 mole %, ethyl acrylateunits of 7.93 mole % and maleic anhydride units of 0.21 mole %.

B-2

A copolymer consisting of ethylene units of 97.20 mole %, glycidylmethacrylate units of 2.80 mole %.

B-3

An modified polypropylene which is modified by the reaction extrusiontechnique, and in which 0.4 mole % of maleic anhydride units aregrafted.

(Examples 1-6 and Comparative Example 1)

The maleimide/isobuthene copolymers and olefin resins prepared in theReference Example were previously shaken and blended in the form ofpowder or pellet of the resin compositions shown in Table 1, and thenkneaded and extruded using a biaxial extruder (Laboplastomill; ToyoSeiki Co., Ltd.) twice at 260° to 320° C. to form pellets. The resultingpellets were injection-molded using an injection molding press(Panajection; Matsushita Electric Industrial Co., Ltd.) at cylindertemperatures of 260° to 350° C. and mold temperatures of 100° to 140° C.to prepare samples for measuring physical properties. The obtainedresults are shown in Tables 1 to 4.

                  TABLE 1                                                         ______________________________________                                                   Maleimide copolymer                                                                         Olefin resin                                                    (% by weight) (% by weight)                                        ______________________________________                                        Example                                                                       1            A-1 (80)        B-1 (20)                                         2            A-1 (75)        B-2 (25)                                         3            A-1 (85)        B-3 (15)                                         4            A-2 (80)        B-1 (20)                                         5            A-3 (75)        B-1 (25)                                         6            A-4 (80)        B-2 (20)                                         Comparative Example                                                           1             A-4 (100)      --                                               ______________________________________                                    

                  TABLE 2                                                         ______________________________________                                                 Heat                       Izod                                               distortion Flexural Flexural                                                                             impact                                             temperature                                                                              Stiffness                                                                              modulus                                                                              strength                                  Sample   (°C.)                                                                             (kg/cm.sup.2)                                                                          (kg/cm.sup.2)                                                                        (kg · cm/cm)                     ______________________________________                                        Example                                                                       1        157        1020     38000  32                                        2        152        920      34000  48                                        3        155        780      33000  18                                        4        155        920      35000  24                                        5        180        780      25000  12                                        6        153        730      31000  8                                         Comparative                                                                   Example                                                                       1        158        1350     48500  2                                         ______________________________________                                    

                  TABLE 3                                                         ______________________________________                                                 Coefficient of                                                                linear thermal  Molding  Dimensional*                                         expansion       shrinkage                                                                              change rate                                 Sample   (× 10.sup.-5 cm/cm °C.)                                                          (%)      (%)                                         ______________________________________                                        Example                                                                       1        5.0             0.4      0.04                                        2        5.6             0.5      0.04                                        3        5.1             0.6      0.05                                        4        5.2             0.5      0.04                                        5        5.7             0.5      0.05                                        6        5.2             0.5      0.04                                        Comparative                                                                   Example                                                                       1        4.8             0.4      0.08                                        ______________________________________                                         *After immersion in water at 23° C. for 24 hours.                 

                  TABLE 4                                                         ______________________________________                                               Before irradiation                                                                          After irradiation                                                 flexural Izod impat flexural                                                                             Izod impact                                        stiffness                                                                              strength   stiffness                                                                            strength                                  Sample   (kg/cm.sup.2)                                                                          (kg · cm/cm)                                                                    (kg/cm.sup.2)                                                                        (kg · cm/cm)                     ______________________________________                                        Example                                                                       1        1020     32         1100   32                                        2        920      48         930    49                                        3        780      18         760    16                                        4        920      24         920    25                                        5        780      12         730    10                                        6        730      8          730    7                                         Comparative                                                                   Example                                                                       1        1350     2          1380   2                                         ______________________________________                                    

(Reference Example 2) Preparation of N-alkyl-substitutedmaleimide/olefin copolymers

A-5

Into art autoclave (50 liters) having a stirring machine,nitrogen-introducing tube, thermometer and deaerating tube were placed2780 g (25 mole) of N-methyl maleimide, 65 g (0.5 mole) of2-hydroxyethyl methacrylate, 3.2 g (0.02 mole) of2,2'-azobisisobutyronitrile (AIBN) and 35 liters of dioxane. After themixture was purged with nitrogen several times, 5610 g (100 mole) ofisobuthene was added, and then reacted at 60° C. for 12 hours.

The reaction contents were poured into ethanol to separate out apolymer. The polymer was dried under reduced pressure at 60° C. for 24hours, with the yield of 4180 g. By subjecting the resulting polymer toelemental analysis and ¹ N-NMR spectrometry, it was found that theprepared polymer contained the maleimide units of 49.5 mole % andglycidylmethacrylate units of 0.8 mole %. The resulting polymer had amolecular weight (MW) of 232000.

A-6

Into the same reactor s used in A-5 were placed 2780 g (25 mole) ofN-methyl maleimide, 49 g (0.5 mole) of maleic anhydride 3.2 g (0.02mole) of 2,2'-azobisisobutyronitrile (AIBN) and 35 liters of dioxane.After the mixture was purged with nitrogen several times, 5610 g (50mole) of isobuthene was added, and then reacted at 60° C. for 12 hours.

The reaction contents were poured into ethanol to separate out apolymer. The polymer was dried under reduced pressure at 60° C. for 24hours, with the yield of 4182 g. By subjecting the resulting polymer toelemental analysis and ¹ N-NMR spectrometry, it was found that theprepared polymer contained the maleimide units of 49.0 mole % and maleicanhydride units of 1.0 mole %. The resulting polymer had a molecularweight (MW) of 250000.

A-7

An N-cyclohexyl maleimide/maleic anhydride/isobuthene copolymer wasprepared by the same method as used in A-6 except that N-cyclohexylmaleimide was used in place of N-methyl maleimide.

The results of the prepared polymer by elemental analysis showed thepolymer contained maleimide units of 51 mole % and maleic anhydrideunits of 1.0 mole %. The resulting polymer had a molecular weight (MW)of 197000.

A-8

An N-methyl maleimide/isobuthene copolymer was prepared by the samemethod as used in A-5 without 2-hydroxyethyl methacrylate. The preparedpolymer had maleimide units of 50 mole % and a molecular weight (MW) of240000.

Modified elastomers

B-4

An acrylonitrile/buthadiene/glycidyl methacrylane copolymer was preparedby the publicly known emulsion polymerization. The resulting copolymerconsisted of acrylonitrile of 35 mole %, buthadiene of 62 mole %, andglycidyl methacrylate of 3 mole %, with Mooney viscosity of 44.

B-5

There as used a commercial available acrylonitrile/buthadiene rubber(Japan Synthetic Lubber Co., Ltd.), with Mooney viscosity of 45.

B-6

A modified copolymer consisting of ethyl acrylate of 60 mole %, bury1acrylate of 38 mole %, and glycidyl methacrylate of 2 mole % wasprepared by the publicly known suspension polymerization.

B-7

A copolymer consisting of ethyl acrylate of 60 mole %, and bury1acrylate of 40 mole % was prepared by the publicly known suspensionpolymerization.

B-8

A modified elastomer was prepared using anethylene/propylene/ethylidenenorbornene elastomer having 1.5 mole % ofmaleic anhydride graft-polymerized by the reaction extrusion method.

B-9

There was used a commercially available ethylene/propylene rubber (JapanSynthetic Lubber Co., Ltd. ), with Mooney viscosity of 42.

(Examples 7-11 and Comparative Examples 2-5)

The maleimide copolymers and modified elastomers were previously shakenand blended in the form of powder or pellet of the resin compositionsshown in Table 5, and then kneaded and extruded using a biaxial extruder(Laboplastomill; Toyo Seiki Co., Ltd. ) twice at 260° to 320° C. to formpellets. The resulting pellets were injection-molded using an injectionmolding press (Panajection; Matsushita Electric Industrial Company Co.,Ltd.) at cylinder temperatures of 260 to 350° C. and mold temperaturesof 100° to 140° C. to prepare samples for measuring physical properties.

The heat distortion temperature, coefficient of linear thermalexpansion, flexural stiffness and flexural modulus, and izod impactstrength of the prepared samples were determined according to ASTM D648,ASTM D694, ASTM D790 and ASTM D256, respectively. The obtained resultsare shown in Table 6.

The interface microstructures of the samples obtained by Example 9 andComparative Example 5 are shown by FIG. 1 and FIG. 2 respectively. Formthe photographs it is understood individual components are more finelydispersed in Example 9 than in Comparative Example 5.

                  TABLE 5                                                         ______________________________________                                                   Maleimide copolymer                                                                         Elastomer                                                       (% by weight) (% by weight)                                        ______________________________________                                        Example                                                                       7            A-5 (80)        B-4 (20)                                         8            A-5 (75)        B-6 (25)                                         9            A-5 (85)        B-8 (15)                                         10           A-6 (70)         B-8 (30)*                                       11           A-7 (80)        B-6 (20)                                         Comparative Example                                                           2             A-8 (100)      --                                               3            A-8 (80)        B-5 (20)                                         4            A-8 (75)        B-7 (25)                                         5            A-8 (85)        B-9 (15)                                         ______________________________________                                         *5000 ppm diaminodiphenyl ether was blended.                             

                                      TABLE 6                                     __________________________________________________________________________               Heat distortion                                                                       Coefficient of                                                                            Flexural                                                                           Flexural                                                                           Izod impact                                     temperature                                                                           linear thermal expansion                                                                  stiffness                                                                          modulus                                                                            stregth                              Sample     (°C.)                                                                          (× 10.sup.-5 cm/cm °C.)                                                      (kg/cm.sup.2)                                                                      (kg/cm.sup.2)                                                                      (kg · cm/cm)                __________________________________________________________________________    Example                                                                       7          160     5.1         920  35000                                                                              28                                   8          157     5.2         850  29000                                                                              45                                   9          158     5.0         820  27000                                                                              35                                   10         156     5.1         820  27000                                                                              52                                   11         178     5.5         780  24000                                                                              21                                   Comparative Example                                                           2          158     4.9         1200 48000                                                                              2                                    3          152     5.3         330  29000                                                                              3                                    4          142     7.0         280  20000                                                                              3                                    5          148     6.8         460  21000                                                                              2                                    __________________________________________________________________________

(Reference Example 3)

Preparation of N-alkyl-substituted maleimide/olefin copolymers

A-9

Into an autoclave (50 liters) having a stirring machine,nitrogen-introducing tube, thermometer and deaerating tube were placed2780 g (25 mole) of N-methyl maleimide, 3.2 g (0.02 mole) of2,2'-azobisisobutyronitrile (AIBN) and 40 liters of dioxane. After themixture was purged with nitrogen several times, 2805 g (50 mole) ofisobuthene was added, and then reacted at 60° C. for 12 hours.

The reaction contents were poured into ethanol to separate out apolymer. The resulting polymer was purified by reprecipitation withdioxane/ethanol, and then dried under reduced pressure at 60° C. for 24hours, with the yield of 4030 g. By subjecting the resulting polymer toelemental analysis (C: 64.7% by weight; H: 7.8% by weight; and N: 8.4%by weight), it was found that the prepared polymer contained themaleimide units of 50 mole % and a molecular weight of 223000.

A-10

Into the same autoclave as used in A-9 were placed 2780 g (25 mole) ofN-methyl maleimide, 71 g (0.5 mole) of glycidyl methacrylate, 3.2 g(0.02 mole) of 2,2'-azobisisobutyronitrile (AIBN) and 35 liters ofdioxane. After the mixture was purged with nitrogen several times, 5610g (100 mole) of isobuthene was added, and then it was reacted at 60° C.for 12 hours.

The reaction contents were poured into ethanol to separate out apolymer. The polymer was dried under reduced pressure at 60° C. for 24hours, with the yield of 4175 g.

By subjecting the resulting polymer to elemental analysis and ¹ N-NMRspectrometry, it was found that the prepared polymer contained themaleimide units of 49.5 mole % and glycidyl methacrylate units of 0.8mole %. The resulting polymer had a molecular weight (MW) of 213000.

A-11

Into the same autoclave as used in A-9 were placed 2780 g (25 mole) ofN-methyl maleimide, 49 g (0.5 mole ) of maleic anhydride, 3.2 g (0.02mole) of 2,2'-azobisisobutyronitrile (AIBN) and 35 liters of dioxane.After the mixture was purged with nitrogen several times, 5610 g (100mole) of isobuthene was added, and then it was reacted at 60° C. for 12hours.

The reaction contents were poured into ethanol to separate out apolymer. The polymer was dried under reduced pressure at 60° C. for 24hours, with the yield of 4182 g.

By subjecting the resulting polymer to elemental analysis and the acidanhydride whose groups were methyl-esterificated to ¹ N-NMRspectrometry, it was found that the prepared polymer contained themaleimide units of 49.0 mole % and maleic anhydride units of 1.0 mole %.The resulting polymer had a molecular weight (MW) of 250000.

A-12

An N-cyclohexyl maleimide/glycidyl methacrylate/isobuthene copolymer wasprepared by the same method as used in A-10 except that N-cyclhexylmaleimide was used in place of N-methyl maleimide.

The results of the prepared polymer by elemental analysis and ¹ N-NMRspectrometry showed the polymer contained maleimide units of 51 mole %glycidyl methacrylate units of 0.6 mole %. The resulting polymer had amolecular weight (MW) of 277000.

Polyamides and elastomers

B-10

Nylon 6 (UBE Nylon 1013 B, UBE INDUSTRIES LTD.)

B-11

Nylon 66 (UBE Nylon 2020 B, UBE INDUSTRIES LTD.)

C-1

A copolymer consisting of ethylene units of 91.86 mole. %, ethylacrylate units of 7.93 mole % and maleic anhydride units of 0.21 mole %.

C-2

A modified ethylene/propylene elastomer in which an ethylene/propylenecopolymer consisting of ethylene units of 75 mole % and propylene unitsof 25 mole % and maleic anhydride of 1 mole % is graft-polymerized bythe reaction extrusion technique.

C-3

A copolymer consisting of ethyl acrylate units of 60 mole %, butylacrylate units of 38 mole %, and glycidyl methacrylate units of 2 mole%.

(EXAMPLE 12)

The N-methyl maleimide/isobuthene copolymer (A-9), polyamide resin(B-10) and elastomer (C-3) prepared in the Reference Example 3 werepreviously shaken and blended in the form of powder or pellet withcomposition shown in Table 1, and then kneaded and extruded using abiaxial extruder (Laboplastomill; Toyo Seiki Co., Ltd.) under theatomosphere of nitrogen twice at 240° to 280° C. to form pellets. Theresulting milk-white pellets were injectionmolded using an injectionmolding press (Panajection; Matsushita Electric Industrial Co., Ltd.) atinjection molding temperatures of 300° C. and molded at moldtemperatures of 100° C. to prepare samples for measuring physicalproperties. The obtained results are shown in Table 8.

(Examples 13-17 and Comparative Examples 6-7)

As in Example 12, the resin compositions shown in Table 7 weremelt-kneaded at 260° to 350° C. to form pellets, which wereinjection-molded at cylinder temperatures of 260° to 350° C. and moldtemperatures of 80° to 140° C. to prepare samples. These samples weremeasured for physical properties. The obtained results are shown inTable 8.

                  TABLE 7                                                         ______________________________________                                               Maleimide Amide                                                               copolymer resin       Elastomer                                               (% by weight)                                                                           (% by weight)                                                                             (% by weight)                                    ______________________________________                                        Example                                                                       12        A-9 (32)   B-10 (55)   C-3 (10)                                     13       A-10 (75)   B-10 (53)   C-1 (15)                                     14       A-11 (25)   B-10 (63)   C-2 (12)                                     15       A-10 (45)   B-11 (45)   C-2 (25)                                     16       A-12 (35)   B-11 (40)   --                                           17       A-11 (38)   B-11 (62)   --                                           Comparative                                                                   Example                                                                        6       --          B-10 (100)  --                                            7       --          B-11 (100)  --                                           ______________________________________                                    

                                      TABLE 8                                     __________________________________________________________________________               Heat distortion                                                                       Flexural                                                                           Flexural                                                                           Izod impact strength (kg · cm/cm)                  temperature                                                                           stiffness                                                                          modulus                                                                            before   after                                   Sample     (°C.)                                                                          (kg/cm.sup.2)                                                                      (kg/cm.sup.2)                                                                      irradiation                                                                            irradiation                             __________________________________________________________________________    Example                                                                       12         160     1220 38000                                                                              25       23                                      13         156     1020 35000                                                                              38       39                                      14         155     880  33000                                                                              22       22                                      15         157     920  35000                                                                              24       21                                      16         181     780  28000                                                                              14       12                                      17         160     1260 40000                                                                              11       12                                      Comparative Example                                                            6         60      1100 29000                                                                              6        --                                       7         70      1100 29000                                                                              3        --                                      __________________________________________________________________________

(Reference Example 4)

Preparation of N-alkyl-substituted maleimide/olefin copolymers

A-13

Into an autoclave (30 liters) having a stirring machine,isobuthene-introducing tube, thermometer and deaerating tube were placed1180 g of N-methyl maleimide, 153 g of 2-hydroxyethyl methacrylate, 8 gof perbutyl neodecanate and 15 liters of a toluene/methanol-mixedsolvent (an weight ratio of 1:1). After the mixture was purged withnitrogen several times, 8.5 liters of liquefied isobuthene was added,and then reacted at 60° C. for 12 hours.

The particulate polymer obtained from the reaction was separated out bycentrifugation and dried under reduced pressure at 60° C. for 24 hours,with the yield of 1770 g. The resulting polymer was reprecipitated witha chloroform/methanol solvent; then by subjecting the polymer toelemental analysis and ¹ N-NMR spectrometry, it was found that theprepared polymer contained the maleimide units of 49.5 mole %,2-hydroxyethyl methacrylate units of 1.0 mole % and isobuthene units of49.5 mole %. The resulting polymer had a molecular weight (MW) of265000.

A-14

Into the same reactor as used in A-13 were placed 1180 gN-methylmaleimide, 23 g of maleic anhydride, 8 g of perbutyl neodecanateand 15 liters of a toluene/methanol-mixed solvent (an weight ratio of1:1). After the mixture was purged with nitrogen several times, 8.5liters of liquefied isobuthene was added, and then reacted at 60° C. for12 hours.

The particulate polymer obtained from the reaction was separated out bycentrifugation and dried under reduced pressure at 60° C. for 24 hours,with the yield of 1750 g. By subjecting the resulting polymer toelemental analysis, and by subjecting the maleic anhydride portion ofthe polymer to ¹ N-NMR spectrometry, it was found that the preparedpolymer contained the maleimide units of 49 mole %, maleic anhydrideunits of 1.0 mole % and isobuthene units of 50 mole %. The resultingpolymer had a molecular weight (MW) of 270000.

Polyester resin

B-12

Polybuthylene terephthalate (UBE Nylon 2020 B, NOVADUR, Mitsubishi KaseiCorp.)

Elastomers

C-4

A copolymer consisting of ethylene units of 97.20 mole % and glycidylmethacrylate units of 2.80 mole %.

C-5

An ethylene/propylene elastomer consisting of ethylene units of 73% byweight and propylene units of 27% by weight which was modified with 0.5%by weight.

(Examples 18-21 and Comparative Example 8)

The maleimide-isobuthene copolymers, polybuthylene terephthalate resinsand elastomers shown in Reference Example 4 were previously shaken andblended in the form of powder or pellet of the resin compositions(weight ratio) shown in Table 9, and then kneaded and extruded using abiaxial extruder (Laboplastomill; Toyo Seiki Co., Ltd.) twice at 260° to320° C. to form pellets. The resulting pellets were injection-moldedusing an injection molding press (Panajection; Matsushita ElectricIndustrial Co., Ltd.) at cylinder temperatures of 260° to 350° C. andmold Temperatures of 100° to 140° C. to prepare samples for measuringphysical properties. The obtained results are shown in Table 10.

                  TABLE 9                                                         ______________________________________                                               Maleimide Amide                                                               copolymer resin       Elastomer                                               (% by weight)                                                                           (% by weight)                                                                             (% by weight)                                    ______________________________________                                        Example                                                                       18       A-13 (35)   B-12 (55)   C-4 (10)                                     19       A-13 (40)   B-12 (45)   C-4 (15)                                     20       A-14 (45)   B-12 (43)   C-5 (12)                                     21       A-14 (38)   B-12 (45)   C-5 (17)                                     Comparative                                                                   Example                                                                        8       --          B-12 (90)   C-5 (10)                                     ______________________________________                                    

                  TABLE 10                                                        ______________________________________                                                 Heat                       Izod                                               distortion Flexural Flexural                                                                             impact                                             temperature                                                                              stiffness                                                                              modulus                                                                              strength                                  Sample   (°C.)                                                                             (kg/cm.sup.2)                                                                          (kg/cm.sup.2)                                                                        (kg · cm/cm)                     ______________________________________                                        Example                                                                       18       138        1220     35000  24                                        19       145        960      34000  29                                        20       150        1020     33000  20                                        21       145        880      30000  25                                        Comparative                                                                   Example                                                                        8       54         680      20000  13                                        ______________________________________                                    

What is claimed is:
 1. A heat-resistant resin composition comprising:(a)1 to 99% by weight of a resin containing 30 to 98 mole % of component(I): ##STR5## wherein R₁ is an alkyl group having 1 to 18 carbon atomsor a cycloalkyl group having 3 to 12 carbon atoms; and70to 2 mole % ofcomponent II: ##STR6## wherein R₂ is hydrogen or an alkyl group having 1to 8 carbon atoms, and R₃ and R₄ are independently alkyl groups having 1to 8 carbon atoms, wherein components I and II are each contained in thewhole polymer, its weight-average molecular weight converted into thatof polystyrene being 1×10³ to 5×10⁶ ; (b) 0 to 40% by weight of anelastomer; and (c) 1 to 99% by weight of a polyester resin.
 2. Theheat-resistant resin composition as claimed in claim 1 wherein R₁ ismethyl, ethyl, isopropyl or cyclohexyl.
 3. The heat-resistant resincomposition as claimed in claim 1 wherein R₂ is hydrogen, and R₃ and R₄are both methyl.
 4. The heat-resistant resin composition as claimed inclaim 1 wherein said olefin resin is a polyethylene, a polypropylene ora poly-4-methyl-1-pentene.
 5. The heat-resistant resin composition asclaimed in claim 4 wherein said polyester resin is a polybutyleneterephthalate, a polyethylene terephthalate, a polyarylate or aliquid-crystaline polyester.